The OP must be from the future since they feel they need a brand new CB radio "tuned and peaked", although I seemed to have heard that phrase quite often in the past
Anyways, most any CB radio will be fine. One compact solution is the Midland 75-822 which I occasionally use. Perhaps that mic hole on the radio you have could be bigger, if your audio is low. Otherwise, leave it alone.
What you really should look at is the antenna and mounting location. I recommend a 102" steel whip antenna on a spring mount located directly center of your roof. Anything less than that and I hope you enjoy even more compromise. A proper antenna not only helps with transmit, but receive as well. Still, if you only plan on communicating with another operator at a distance of 1000 yards or less you can probably get away with a compromised antenna in a compromised location.